Sickle cell disease is a group of complex, chronic disorders characterized by hemolysis, acute vaso-occlusive episodes (crises), unpredictable acute complications that can be life-threatening, and the variable development of chronic organ damage. Administration of magnesium sulfate has the potential to reduce hemolysis since it induces negatively charged chloride ions and water entry to the cell. To date only one non-randomized, non-blinded, single arm study with only 19 children evaluated the effect of magnesium on length of stay in the hospital of children with sickle cell disease.